Fujitsu FR20 User Manual
87
4.2
Block Diagram
Figure 4.2-1 shows the block diagram of the external bus interface.
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Block Diagram of External Bus Interface
Figure 4.2-1 Block diagram of external bus interface
+1or +2
write
buffer
buffer
read
buffer
buffer
ADDRESS BUS
DATA BUS
Internal pin control unit
switch
switch
A-Out
M
U
X
X
External DATA Bus
DATA BLOCK
ADDRESS BLOCK
address
buffer
buffer
inpage
shifter
comparator
ASR
AMR
External
Address Bus
CS0X-CS5X
CS1X (Read/Write Control)
RD
WR0, WR1
ALE
registers
&
Control
All Block Control